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* Author: TKruse
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#ifndef PREFER_FORWARD_COST_FUNCTION_H_
#define PREFER_FORWARD_COST_FUNCTION_H_

#include <base_local_planner/trajectory_cost_function.h>

namespace base_local_planner
{

class PreferForwardCostFunction : public base_local_planner::TrajectoryCostFunction
{
public:

    PreferForwardCostFunction(double penalty) : penalty_(penalty) {}

    ~PreferForwardCostFunction() {}

    double scoreTrajectory(Trajectory &traj)
    {
        // backward motions bad on a robot without backward sensors 如果机器人没有看向后面的传感器，强烈不建议后退
        if (traj.xv_ < 0.0) return penalty_;
        // strafing motions also bad on such a robot 惩罚线速度和角速度都很小的运动
        if (traj.xv_ < 0.1 && fabs(traj.thetav_) < 0.2) return penalty_;
        // the more we rotate, the less we progress forward 旋转的越多，前进的越少
        return fabs(traj.thetav_) * 10;
    }

    bool prepare() { return true; };

    void setPenalty(double penalty) { penalty_ = penalty; }

private:
    double penalty_;
};

} /* namespace base_local_planner */
#endif /* PREFER_FORWARD_COST_FUNCTION_H_ */
